Patent GB-498404-A (GB)
Title: Process for the manufacture of derivatives of phenanthrolins
Filed: 1937-07-07
Abstract: Phenanthroline derivatives are manufactured by reacting an o-, m- or p-phenanthroline containing a halogen atom in at least one of the positions 2-, 4-, 21- and 41- (a - and g -positions with regard to the nuclear nitrogen atoms) with an alcohol or phenol compound, e.g. an alkali or alkaline-earth metal a coholate or phenolate, in the presence of an acid binding agent, e.g. an alkali or alkaline - earth metal oxide, hydroxide or carbonate, and a d luent, e.g. the alcohol or phenol itself, or by reacting a phenanthroline containing a hydroxyl group in at least one of the said positions, or a metal compound thereof, with a reactive ester of an alcohol or phenol, e.g. an alkyl halide, preferably an iodide, an allyl or benzyl halide, a dialkyl sulphate or a halogenated aromatic compound in which the halogen atom is activated by other groups, e.g. nitro groups, in the presence of an acid-binding agent.  The products have an anodyne action, and are also suitable as starting materials for chemical p processes.  In examples: (1) 2 : 21-dimethyl-4 : 41-dichloro-p-phenanthroline (obtainable by the action of phosphorus oxychloride on the corresponding 4 : 41-dihydroxy compound) is heated in an autoclave with a solution of potassium hydroxide in methyl alcohol to produce 2 : 21-dimethyl-4 : 41 - dimethoxy - p - phenanthroline; (2) by using a solution of sodium in cyclohexanol there is similarly obtained 2 : 21-dimethyl-4 : 41-bis-cyclohexyloxy - p - phenanthroline; (3) 2 : 21 - dimethyl4 : 41-dichloro-p-phenanthroline is heated with phenol in the presence of potassium carbonate, producing 2 : 21-dimethyl-4 : 41-diphenoxy-p-phenanthroline; there may similarly be prepared 2 : 21-dimethyl-4 : 41-bis- (311- and 411-methyl-, 311 : 511-dimethyl-, and 411-chlorophenoxy)-p-phenanthroline; (4) hydroquinone monomethyl ether similarly yields 2 : 21-dimethyl - 4 : 41 - bis - (411 - methoxyphenoxy) - p - phenanthroline; the corresponding 411-ethoxy and 211-methoxy compounds may be similarly prepared; (5) hydroquinone is similarly reacted, while passing dry carbon dioxide over the mass, to produce 2 : 21 - dimethyl - 4 : 41 - bis - (411-hydroxyphenoxy)-p-phenanthroline; (6) 2 : 21-dimethyl - 4 : 41 - dichloro - p-phenanthroline is heated with m- or p-nitrophenol in the presence of potassium carbonate, yielding 2 : 21-dimethyl-4 : 41-bis-(311- and 411-nitrophenoxy)-p-phenanthroline, which may be reduced to the corresponding amines; (7) p-acetylaminophenol similarly yields 2 : 21-dimethyl-4 : 41-bis-(411-acetylaminophenoxy)-p-phenanthroline, which is also obtainable by acetylating the 411-amino compound of (6); the reverse change may be effected by saponification; there may similarly be prepared 2 : 21-dimethyl-4 : 41-bis-(311-acetylamino- and 311- and 411-methoxyacetylaminophenoxy)-p-phenanthroline; (8) p-hydroxybenzoic acid ethyl ester similarly yields 2 : 21-dimethyl-4 : 41-bis-(411-carbethoxyphenoxy)-p-phenanthroline, which may be saponified with alcoholic potassium or sodium hydroxide to the potassium or sodium salt of the corresponding carboxylic acid; (9) p-hydroxyacetophenone similarly yields 2 : 21-dimethyl-4 : 41-bis-(411 acetophenoxy) - p - phenanthroline; (10) 3-hydroxydiphenylene oxide similarly yields 2 : 21-dimethyl-4 : 41 - bis - (diphenylene - oxide-311-hydroxy)-p-phenanthroline, whilst from b -naphthol there is obtained 2 : 21-dimethyl-4 : 41-bis - (211 - naphthoxy) - p - phenanthroline; (11) 2 : 21-dimethyl-4 : 41-dichloro-p-phenanthroline is heated with a solution of potassium in benzyl alcohol to produce 21 : 21 - dimethyl - 4 : 41-dibenzyloxy - p - phenanthroline; (12) 2 : 21-dichloro - p - phenanthroline (obtainable by chlorinating N : N - dimethyl - 2 : 21 - p - phenanthrolindione with phosphorus pentachloride) is heated with phenol in the presence of potassium carbonate, producing 2 : 21-diphenoxy-p-phenanthroline; (13) 2 - methyl - 4 - chloro - o - phenanthroline (obtainable by chlorinating 2-methyl-4-hydroxy-o-phenanthroline which may be obtained from 8-aminoquinoline by the Conrad - Limpach synthesis) and 2-methyl-4-chloro-p-phenanthroline (obtainable similarly from 6-aminoquinoline) similarly yield 2-methyl-4-phenoxy-o- and p-phenanthroline; (14) 2-chloro-m-phenanthroline (obtainable by the action of phosphorus pentachloride on N-methyl-a -m-phenanthrolone, which may be obtained from N-methyl-m-phenanthrolinium methosulphate, produced by the addition of dimethyl sulphate to m-phenanthroline) similarly yields 2-phenoxy-m-phenanthroline; (15) 2 : 21 - dimethyl-4 : 41-dihydroxy-p-phenanthroline is heated with dimethyl sulphate in the presence of caustic potash lye, producing 2 : 21-dimethyl-4-hydroxy-41-methoxy-p-phenanthroline; (16) benzyl chloride similarly yields 2 : 21-dimethyl-4-hydroxy-41-benzyloxy-p-phenanthroline. Specification 498,405 is referred to.